Unipolar Resistive Switching in ZrO 2 Thin Films

• Published in: Japanese Journal of Applied Physics Vol. 52; no. 4R; p. 41101
• Main Authors: Zhang, Guo-Yong, Lee, Dai-Ying, Yao, I-Chuan, Hung, Chung-Jung, Wang, Sheng-Yu, Huang, Tai-Yuen, Wu, Jia-Woei, Tseng, Tseung-Yuen
• Format: Journal Article
• Language: English
• Published: 01.04.2013
• ISSN: 0021-4922; 1347-4065
• DOI: 10.7567/JJAP.52.041101

Unipolar resistive switching behaviors including bistable memory switching and monostable threshold switching were found in ZrO 2 thin films fabricated by a simple sol–gel method with the Ti/ZrO 2 /Pt structure. The multilevel resistive switching behaviors were also revealed by varying the compliance current from 9 to 38 mA. Physical mechanisms based on a conductive filament model were proposed to explain the resistive switching phenomena and the device breakdown. A figure of merit Z = ρ a /ρ f was defined as a criterion for evaluating OFF/ON resistance ratio, where ρ f and ρ a represent the resistivities of the conductive filament and the fracture region of the filament, respectively. The advantages such as unipolar resistive switching, multilevel resistive switching, good scalability, low operation voltage (<5 V), high OFF/ON resistance ratio (>10 3 ), nondestructive readout, long retention (>10 4 s), and simple fabrication method make the ZrO 2 -based resistive switching device a promising candidate for next-generation nonvolatile memory applications.